Imaging with 11B of intact tissues using magnetic resonance gradient echoes

Boron neutron capture therapy (BNCT) is a proposed method of treating Glioblastoma Multiforme. BNCT is based on 10B intake by the tumor and in-situ activation by neutron beam. It is estimated that to have successful BNCT, a 10B delivery mechanism must deposit 20 ppM or more of 10B within the tumor. To study and understand this delivery mechanism, 11B can be used instead of 10B. The pharmacokinetics of any compound using 11B will be the same as 10B. The advantage of using 11B over 10B is its greater nuclear magnetic resonance sensitivity for both spectroscopy and imaging. The use of 11B imaging to detect and quantitate boron uptake non-invasively in animal tumor modes will facilitate continued work with 10B. Preliminary work has shown that 11B nuclear magnetic resonance (NMR) spectroscopy (nonlocalized) can detect 11B in intact mouse tissues and the area under the boron peak correlates with the total boron content (correlation coefficient of 0.997). Once the ability to non-invasively measure the boron compound is established using magnetic resonance imaging (MRI) combined with spectroscopy, we will be able to address the following questions: (1) what is the optimum method of boron administration for maximum tumor selective uptake, (2) at what time is peak tumor boron concentration after infusion, and (3) what is the dose distribution in the head (based on neutron radiation and boron concentration)? The purpose of this study was to test the feasibility of imaging 11B in intact tissues using magnetic resonance